Dry suit

ABSTRACT

The dry suit is preferably manufactured as a one-part combination suit from a three-layer, waterproof but air-permeable fabric laminate with max. mass per unit area of 220 gr/m2, and it seamlessly encloses the feet as well. A waterproof zip fastener extends from the crotch to the top of the collar. The sleeves are each fitted with a waterproof zip fastener extending backward from the front edge of the cuff along the forearm. With said waterproof zip fastener, the collar and chest area as well as the sleeves and front sleeves can be opened to a certain extent, providing an effective cooling function, which makes wearing the dry suit in non-critical mission phases significantly more comfortable and less tiring. In addition, said dry suit has a total weight of less than 1.5 kg and is correspondingly easy to wear on the body.

This invention relates to a comfortable, light and breathable dry suit for keeping persons having fallen into the water dry to delay their life-menacing hypothermia. Among experts one speaks of Immersion Protection Suits (IPS).

An immersion suit or survival suit, is a special kind of waterproof dry suit. It is intended to protect people who have fallen into cold water as a result of an accident, usually after a sinking or capsized ship has been abandoned, or in the military sector after a crash into the water or an emergency landing of an aircraft on water. Such a dry suit should maintain the body heat within the suit and keep the user dry until he or she is rescued from the cold water. These dry suits are tailored to the wearer's body and must be worn by a crew as a precautionary measure if there is the danger of falling into the water during a mission. It is therefore important that these suits are as light as possible, as well as quickly and easily put on and comfortable to wear. It is known that a person's chance of survival when he or she has fallen into the water can be significantly increased essentially by staying dry and maintaining the body temperature, because then a hypothermia can be postponed.

Conventional dry suits are usually made of reinforced neoprene and have a face seal and flap, finger gloves, waterproof zip fasteners, ankle cuffs, neoprene pockets and reflective stripes, and they are to limit the wearer's freedom of movement as little as possible. They must comply with the provisions of the International Convention for the Safety of Life at Sea (SOLAS) as to hypothermia, and their use is intended primarily for personnel on board military aircraft, military ships or military boats, ferries, offshore drilling rigs, lifeboats, fast-rescue boats and for general commercial use.

The challenges in constructing a dry suit are the various conflicts of aims. The suit should provide optimum protection against heat loss and wetness. However, the better it fulfils these characteristics, the more uncomfortable it is to wear, as long as its actual function does not matter. Because of the waterproofness, for example when using neoprene, sweating or breathing of the body's skin is impossible. Correspondingly, the heat accumulates in the body, which is very unpleasant. The better the thermal insulation, the less comfortable the suit is to wear. Many dry suits with thick layers of thermal insulation materials are so stiff and cumbersome that they can hardly be put on by the users themselves. They need helpers to put on the suit. If, for example in the case of aircraft crews, a dry suit has to be worn during the preparation phase or briefing for a flight as well as during debriefing, this is usually very uncomfortable for those affected. In the usual suits one sweats, although in principle one can't sweat effectively for the heat dissipation. As soon as one has put on a conventional dry suit, the neck and wrists are sealed waterproof in this suit and any air exchange between the inside and outside, and thus with the body surface, is prevented. This leads to the fact that very soon one has a moist or wet body surface and has to suffer from a heat accumulation. Wearing such a dry suit is therefore very unpleasant in the long run and considerably impairs well-being and performance, a fact every naval pilot will immediately confirm.

The object of this invention is therefore to create a dry suit which, in addition to the function of keeping the wearer dry in water and insulating the heat in accordance with the existing regulations is now considerably lighter and much easier to put on and much more comfortable to wear. Furthermore, the dry suit should be capable of being worn in combination with an acceleration protection suit as one is indicated in WO2012/066114 A1, and it should in any case be capable of being put on and taken off by the user without assistance, and have passive or optionally active cooling functions for the phases of non-functional use.

This object is solved by a dry suit for keeping people having fallen into the water dry by delaying their life-threatening hypothermia, characterized in that it has at least one waterproof zip fastener for putting on and taking off said dry suit, wherein a waterproof zip fastener divides the collar for opening, and that at each of the sleeves a waterproof zip fastener extends along the forearm for opening the waterproof cuffs so that the entire suit can be worn open at collars and cuffs during non-critical mission phases and thus allows an air exchange with the surface of the body, and that it can quickly be brought from this state to a waterproof state by closing all waterproof zip fasteners.

In the figures, this suit is pictured in two versions and described hereafter, and its function explained.

There are shown:

FIG. 1 The dry suit is designed as a one-piece combination suit, in donned state, as viewed from the front;

FIG. 2 The dry suit is as a tow-piece suit, except for a textile material bridge, having jacket and trousers, in donned state, as viewed from the front.

As can be seen in FIG. 1, the suit in this example is designed as a combination suit 1, i.e. it forms a one-piece suit. As a special feature, this suit consists of a three-layer, flame-resistant, waterproof, breathable and incident flow-proof fabric laminate with a weight per unit area of merely 220 grams/m². This fire-retardant fabric laminate consists of a tear- and flame-resistant fabric on the outside, followed by a glue layer, then a membrane with a microporous structure, for example based on polytetrafluoroethylene, with more than 10 million pores per mm² so that this membrane is waterproof but vapor-permeable. Then comes another glue layer, followed by a fabric with aramid fibers (Kevlar®), which is particularly light, about 40 gr./m²±10%, and serves as a protective layer for the inner membrane. Hence the fabric laminate can withstand a pressure column of up to 10 meters and is therefore highly watertight or waterproof as well as incident flow-resistant. By using this fabric laminate, a low overall weight of the entire dry suit of less than 1.5 kg is achieved, which has hardly been thought possible so far. This in turn significantly increases the wearing comfort of this dry suit. Experiments have shown that it adds so little bulkiness to the body that it can even be worn under an ordinary street suit without the viewer noticing it. The fabric of the dry suit has to be incident flow-resistant in order that the dry suit can withstand very high incident-flow speeds of up to 600 knots (kn) or 1111 km/h, as these occur in the event of an ejector seat ejection and act on the pilot. This incident flow-resistance is achieved by the mentioned high tear resistance which is offered by the flame-retardant thin outer fabric.

To put on the dry suit, one slips one's legs and feet into the trouser joints 2, and this part hereafter wraps the legs and feet of the wearer already waterproof so that the wearer could stand knee-deep to hip-deep in water because the trouser joints 2 made of waterproof three-layer fabric seamlessly merge into foot bindings 3. The suit is easy to put on because a waterproof zip fastener 4 extends from the area of the crotch to the top of collar 5. To put on the upper-body garment 6, one opens along with the front main zip fastener 4 also the two zip fasteners 7 on the cuffs 13 and front sleeves 8. Hereafter one can slip on the upper-body garment 6 and in the process slip one's arms into the sleeves 8. The suit offers at least one waterproof zip fastener chest pocket 15, which can be closed with a waterproof zip fastener 14, as well as another waterproof zip fastener 18, which allows access inside the suit in the chest area. This is in particular necessary if the dry suit is worn over another suit, especially over an acceleration suit. It has been shown that in this case the function of the acceleration protection suit is not impaired by this dry suit being worn over it. Furthermore, the dry suit can optionally have a waterproof trouser pocket 10 which can likewise be closed with a waterproof zip fastener 9.

During preparation and intermediate times, when the suit does not have to be in standby mode, i.e. during uncritical mission phases, this dry suit can be left open at the top of collar 5 and at the front sleeves 8 by not tightening the zip fasteners 7 there completely, but by leaving a section somewhat open as desired, and by leaving the main zip fastener 4 of collar 5 somewhat open at will. Hence an effective passive cooling function is achieved, which is not possible with any other dry suit to date and is probably the most important advantage of this dry suit. Conventional dry suits, once they are put on, namely enclose the neck and wrists in a waterproof manner so that air exchange with the body is no longer possible, which proves to be extremely unpleasant as long as no emergency occurs, which is true for most of the time when such a dry suit is worn. The cooling function of the dry suit presented here by opening collar 5 and cuffs 13 and front sleeve 8, however, offers the user an enormous and highly welcome relief in practice. Due to its cooling function and its special lightness, wearing this dry suit proves to be far more comfortable than closed dry suits of conventional design.

The main zip fastener 4 is closed up to the upper collar edge only shortly before a standby phase. The collar 5 is equipped with an elastic rubber lip 11 at its upper edge, which attaches itself all-round waterproof to the neck of the wearer when the main zip fastener 4 is completely closed. The cuffs 13 are at the front end of the sleeves are executed similarly. They terminate with a rubber lip 12 which runs around the zip fastener. When the zip fasteners 7 on the front sleeves 8 are completely closed toward the front, these rubber lips 12 close behind the wrist around the forearms in a waterproof manner.

As FIG. 2 shows, the dry suit can be produced in a variant as effectively a two-piece suit, with a jacket and trousers 17 attached to it by a textile material bridge. The trousers and the jacket are connectable in a waterproof manner by a waterproof zip fastener 16, which runs around the hip overlapping somewhat. This design offers a further cooling function in the hip area, because when this zip fastener 16 is more or less opened, a very welcome cooling function is hence achieved in the area of the abdomen, hip and lower back. Especially in the area of the lower back one tends to sweat particularly heavily. Apart from that, this suit is constructed identically to the one corresponding to FIG. 1, i.e. it also has at least one waterproof breast pocket 15, which can be closed with a waterproof zip fastener 14, and a waterproof zip fastener 18 in the chest area, for reaching into the dry suit from outside. Further, as shown, this suit has a waterproof trouser pocket 10 which can be closed with a waterproof zip fastener.

Hence this dry suit, as presented, is the only known protection suit against cold and water for aircraft crews which, in the context of flight preparations and flight post-processing and debriefings, can be worn with the collar open to the lower abdomen and with open cuffs 13 and front sleeves and nevertheless offers the wearer the necessary cold water-protection in an emergency by quickly closing the waterproof zip fasteners.

Furthermore, because this dry suit for the first time consists of a comparatively thin, three-layer fabric laminate, it weighs less than 1.5 kg and is therefore so light and hardly bulky that it can be worn over an acceleration protection suit, and the function of this G-suit is not impaired if it is constructed according to the design as disclosed in WO2012/066114. If it is furthermore combined with the features of a cooling suit, i.e. equipped with flat cooling channels on its inner side, which can be supplied for example at the hip area from a hose sleeve opening waterproof outwardly via a hose from a portable pressurized gas cylinder with expanded and thus cool gas, preferably with cool air, it also offers, in addition to protection from cold and moisture, an active, highly effective cooling system for the periods in which it is worn as a protective suit merely as a precaution. The gas and air ducts are then led to all highly perspiring body parts and have outlet openings to transport heat away from there. These points are located especially at the lower back, at the hips, in the hollows of the knees, at the neck and in the chest area, in the armpits, arm joints as well as at the front sleeves which face the inner sides of the wearer's forearms. The heat absorbed by this cooling gas or by the cooling air is then transported outward through the cuffs 13 kept open and the opened collar 5 as long as the dry suit is not used as such. Hence this offers a system which is even more comfortable and less heat-intensive for intercontinental flights, as well as for operations in the tropics and in the polar regions.

The pilot or other crew members do not need any help and can put on or take off the suit by themselves. The very light and at the same time extremely heavy-duty 3-layer fabric laminate was developed especially for this dry suit. This innovative fabric laminate leads to a weight reduction and at the same time to high strength and durability. In addition to the waterproofness and a certain air permeability, the result is a weight of less than 1.5 kg for the entire suit.

This dry suit includes synthetic, waterproof zip fasteners, covered with fire-resistant fabric, which allow the suit to be worn opened at the neck and arms during the entire pre- and post-flight phase for maximum comfort. The openable sleeves 13 at the neck and the forearms offer significantly increased comfort and enable the longer-term wearing while preserving the performance of the wearer on account of low strain and correspondingly less tiredness of the wearer. The waterproof finish of collar 5 consists of an elastic rubber lip 11 made of neoprene, silicone or a material with comparable properties laminated onto flame-resistant fabric, which is divided by main zip fastener 4, however, seals the neck area when the main zip fastener 4 is closed. Just like the collar 5, the cuffs 13 at the ends of the sleeves consist of such a structure, i.e. a rubber lip 12, which is divisible by the zip fasteners 7, laminated onto a flame-resistant fabric of the cuffs 13, the rubber lip 12 being made of neoprene, silicone or a material with comparable properties.

In combination with the mentioned cooling system having gas or air ducts within the suit 1, prolonged operations are possible even under extreme environmental conditions with high ambient temperature and also in high relative humidity without significant fatigue of the user. Nevertheless, the user is always wrapped in a waterproof and heat-insulating way within seconds, which means that he or she merely needs to completely close the waterproof zip fasteners 4, 7, 9 and 16.

The target groups for the use of such dry suits are mainly the following professions:

-   -   Pilots/crew members of jet-propelled fighter aircraft.     -   Pilots, crew members and passengers of helicopters, transport         aircraft and special aircraft.     -   Crews and passengers of seagoing vessels.     -   Water sportsmen of all kinds (yachtsmen, canoeists, kayakers,         surfers, stand-up paddlers etc.).

LIST OF NUMERALS

-   1 Combination suit -   2 Trouser joints -   3 Foot bindings -   4 Main zip fastener -   5 Collar -   6 Upper-body garment -   7 Zip fastener 7 on the front sleeves -   8 Sleeve -   9 Zip fastener for closable trouser pocket -   10 Closable trouser pocket -   11 Elastic rubber lip on collar 5 -   12 Elastic rubber lips on the cuffs -   13 Cuffs -   14 Waterproof zip fastener for breast pocket -   15 Breast pocket -   16 Zip fastener between jacket and trousers 

1.-12. (canceled)
 13. A dry suit for keeping people having fallen into the water dry by delaying their life-threatening hypothermia, that it is made of a fabric laminate, the same consisting from outside to inside of a tear- and flame-resistant fabric, a waterproof membrane having a microporous structure on the basis of polytetrafluoroethylene and an inner fabric, and that it has waterproof zip fasteners for putting on and taking off and at each of the sleeves a waterproof zip fastener extends along the lower arm, characterized in that the waterproof sealings at the neck and wrist are realized by rubber lips which are each divisible by a waterproof zip fastener, wherein the rubber lips are laminated onto fire-resistant fabric and upon closed zip fasteners are intended to be fitted waterproof at the neck or at the wrists so that the entire suit can be worn open at collars and cuffs during non-critical mission phases and thus an air exchange with the body's surface is possible, and that it can quickly be brought from this state to a waterproof state by closing all waterproof zip fasteners, and that from inside to outside the fabric laminate consists of a tear- and flame-resistant fabric on the outside having 40 gr/m2±10%, followed by a glue layer, then a waterproof but vapor-permeable membrane having a microporous structure on the basis of polytetrafluoroethylene having more than 10 million pores per mm2, then a further glue layer, followed by a fabric having Aramid fibers (Kevlar®) as a protective layer for the inner membrane so that this three-layer, waterproof, fire-resistant and air-permeable fabric laminate has a maximum mass per surface area of 220 g/m2 and the entire dry suit weighs less than 1.5 kg.
 14. The dry suit according to claim 13, characterized in that the three-layer fabric laminate offers such good water resistance and waterproofness that it can withstand a pressure column of up to 10 meters.
 15. The dry suit according to claim 13, characterized in that it is designed as a one-piece combination suit having a waterproof zip fastener which extends from the crotch area up to the upper edge of the collar and divides the same.
 16. The dry suit according to claim 13, characterized in that it is designed as a two-piece suit of trousers and jacket, except for a textile material bridge between trousers and jacket, and that trousers and jacket are connectable in the hip area with a waterproof zip fastener running around the hip, with one side of the zip fastener running along the bottom edge of the jacket and one side of the zip fastener along the waistband, wherein the end regions of the zip fastener overlap laterally offset, including the textile material bridge between the jacket and trousers.
 17. The dry suit according to claim 13, characterized in that it can be worn over an acceleration protection suit of a design according to WO2012/066114 without impairing the function of the acceleration protection suit.
 18. The dry suit according to claim 13, characterized in that it has in the chest area at least one breast pocket which is inwardly recessed and which can be closed with a waterproof zip fastener, as well as a waterproof zip fastener in the chest area for reaching into the donned dry suit when worn over another suit or acceleration protective suit.
 19. The dry suit according to claim 13, characterized in that it has at least one trouser pocket which can be closed with a waterproof zip fastener.
 20. The dry suit according to claim 13, characterized in that the three-layer fabric is designed incident flow-resistant, i.e. it can withstand air currents of up to about 1150 km/h undamaged by having the outer fabric woven from tear-resistant synthetic and aramid fibers (Kevlar®) and being equipped with a protection against splitting of the waterproof zip fastener.
 21. The dry suit according to claim 13, characterized in that its inner side is additionally equipped with flat gas ducts which can be supplied starting from a hose sleeve opening watertight outwardly via a hose from a portable pressurized gas cylinder with a gas which is expanded and thus cooled down, wherein the gas ducts on the inner side of the dry suit are led to the highly perspiring body parts and there have outlet openings to transport heat away from there.
 22. The dry suit according to claim 21, characterized in that the outlet openings of the gas ducts are located especially in the area of the lower back, at the hips, in the hollows of the knees, at the neck and in the chest area, in the armpits, at the arm joints as well as at the front sleeves which face the inner sides of the wearer's forearms so that the heat absorbed by the cooling gas can be transported outward through the open cuffs and the collar as long as the dry suit is used in non-critical mission phases. 